I read a few messages that there is a need to place a series of holes around a circle.
Toward that end I created an EXCEL worksheet that gives the dimensions to locate up to 36 (drilled) holes around the circumference of any size circle. Two inputs are needed (1) number of holes (2) radius of circle.
There is an mpc picture on the worksheet along with the calculations. This is for information only. The picture can be deleted. The EXCEL file is zipped.
I find it helpful to place the (drilled) holes in the upper right quadrant then use the X and Y calcs to ATTACH the hole. (see picture) Use the negative sign when the calc shows a negative number. If all the holes are the same diameter use the copy/paste method for the next hole etc, etc.
With a little imagination any object can be used in place of holes. Of course all this wouldn't be necessary if designer had rectangular and polar array functions.
I hope you find it useful.
Hank